5.4 rough idle

I have had my 1999 F-150 5.4 in for rough idle 3 times and still I am told this is normal. BULL S&*% I even put a glass of water in my console to show the service tech how the water spills out at idle. If you are expereancing a rough idle report it to NHTSA service bulletin database. call 888-327-4236. They will take your complaint and and log it for possible RECALL for this problem.PASS the word to all 5.4 owners who are expereancing this rough idle. O ya keep taking your truck back to service at least once a month until they get tired of us and finally take care of this annoying problem......

I am a tech at a ford dealer . I have run across a few 5.4 's running rough. I have found the right side head cam timing was off by one tooth causing them to idle quite rough at idle with your foot on the brake. But they run fine off idle and have plenty of power. One tooth is just enough to affect the idle without hurting performance. These triton engines are very tricky to time the manuals say the timing mark on the right head should be @11:00 and the left should be @12:00 they state the marks should be approximately 11,12 . Well approximately some times ends up 1 tooth off. Best way to ck the timing is hook up SBDS run a relative compression test if all cylinders on one side are 4-5% low the timing is 1 tooth off. Hope this can help somehow. Good Luck

Well I took a little advice and scheduled my truck to a differant dealer and asked them to check my truck on the SBDS Diagnostics tests. I was told the relitive compression for all 8 cylinders was zero% and the fuel pressure and leak down all passed. The tech told me they did not adjust anything but I now notice my idle raises and lowers with what sounds like a solinoid regulating it. This did help the rough idle slightly. Does any one know what was adjusted to change my idle as I described?

Depending on your computer code, they may have reflashed the ecu. Check under the hood on the plastic cover over the radiator for a
"Re-Program" sticker. Reflashing could affect several operating characteristics of your truck, from idle to shift points, to air/fuel ratio. Ford continuously gets TSB's on reflashing certain codes.
Later
Danny

I am not a tech or claim to know it all. My 1997 5.4 has 60k miles and the engine idles rough every now and then. I put in a can or two of Berrymans B12 and no more problem. I figure the gas we buy today may have something to do with it. Hope this helps you.

Update on what has been happening w/ my 5.4 A Ford rep called me and told me that the 5.4 always had a rough idle and there is no fix. They do know they have a problem they even changed the steering wheel and leather wrapped it to help hide the rough vibration. The oldest trick in the book. They also changed the heads,pistons and changed the wiring harness not to mention various fuel injectors. Still they cannot tame this poorly designed motor. My story started the day my truck was delivered I questioned the rough idle before I signed the papers and the service manager told me it would disapear after break-in. It never disapeared and only got worse. The dealer is denying this and the Ford rep believes this.I know what was said and have no reason to lie. All I wanted was the quality truck I paid for.The dealership that betrayed and misled me is Romeo Ford in Michigan. I strongly recommend that before you sign your final papers make sure your vehicle is 100% accept no verbal promises.
My experance with Ford has been the worst relationship a person could have.I explained to the rep that I set up a stationary dial indicator to mearure the cab movement and he told me this was a primitive test and non conclusive. Sorry I don't have a million dollars to measure interior vibration. But the test I set up proves that my truck does not have similar charictoristics of other trucks on Ford lots.
I know this is a Ford web page and hate to dis Ford but please take all this into concideration before spending your hard earned money on a Ford product. Thank you for your time. Replies are welcome

I have ZERO trouble with my 5.4. It now has over 52K miles and still purrs like a kitten. It's seen 5 thousand rpm in 4 Low and 4600 rpm at over 110 mph. Yes, it has a chip. I have traveled for hours over 80 mph. So far NO PROBLEMS. I'd buy it again.

i have a '00 F150 w/5.4 and mine has a slight rough idle while i'm in traffic...seems like more of a plug misfire than anything. the truck has almost 59K miles and i just bought it so i don't know when the last time was that it was tuned. i guess that will be high on the list of things to do soon.

Well I can't help any but a friend of mine has a 2001 F-150 XLT Ext. cab with the 5.4 and 3.55 gears. The truck has 44k miles and he has hot rodded and lead footed it through every mile. The truck has been wrecked twice and driven through high water countless times, he even roasted the first transmission at 23k miles from flood water damage. He's even been neglectful enough to hold off oil changes for a 1000 miles or so, even driving the truck after it's been sitting and not started for three months.

Yet his 5.4 still purrs like the day he drove the truck off the dealer's lot. Doesn't make a lick of sense now does it?

I Have had no problems with my 2000 Flareside 5.4L
It has 23,900 miles on it. I pull a trailer with it too
When I change the oil I always add a bottle of good quality
fuel injector cleaner and I am completely satisfied with my truck.
I live in North Central Pennsylvania where the temperatures can drop below zero which it recently has, and I have no problems
starting my truck. It fires immediately every time!
Long live the 5.4!!

This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor Company.